Run2 ESD to Run3 AOD converter

This is an helper executable to read Run2 ESD data and pump it to stdout as a set of Arrow BatchRecords. This is to be coupled with some yet to happen development in DPL to chunk the stream into messages.

The scripts/pythonReader.py python script on the other hand is an initial attempt to demonstrate how this can also be processed using python + pandas.

The python example can be run by doing:

run2ESD2Run3AOD ~/work/active/data/AliESDs_15000246751039.3412.root | scripts/pythonReader.py

and then you should find a few figure*.pdf files with some random plots in your current path.

In order to validate the conversion you can use the validateAODStream helper.

Updating to a given version of AliRoot / O2

The converter embeds a copy of the relevant AliRoot files to be able to read ESD event content. It also contains a copy of the O2 arrow based utilities. In order to update to the latest greatest version you need to:

git clone https://github.com/AliceO2Group/AliceO2 O2
git clone https://github.com/AliceO2Group/Run2ESDConverter O2
git clone https://github.com/alisw/AliRoot
cd Run2ESDConverter
rm -rf Run2DataModel/src
./copyArrowDataModel.sh
./copyAliESDEvent.sh